Solid blends of peroxy compounds and phosphate containing detergent bases

ABSTRACT

A PARTICULATE DETERGENT COMPOSITION COMPRISING PHOSPHATE CONTAINING DETERGENT BASE AND A SOLID BLEND OF PEROXY COMPOUNDS COMPRISING INORGANIC PEROXIDIC COMPOUNDS SELECTED FROM THE GROUP CONSISTING OF PERCARBONATES, PERBORATES IN THE FORM OF AN ACTIVE OXYGEN CONTAINING MATERIAL CONSISTING OF SUBSTANTIALLY REGULAR PARTICLES OF WHICH AT LEAST 80% BY WEIGHT HAVE DIAMETERS WHICH VARY BY NOT SUBSTANTIALLY MORE THAN 25% FROM THE AVERAGE MEAN DIAMETER OF THE INORGANIC PEROXY COMPOUND PARTICLES. THE PERBORATE AND PERCARBONATE COMPONENTS MANIFEST THE BULK DENSITY OF 1:3 TIMES THAT OF THE DETERGENT BASE AND AN AVERAGE MEAN PARTICLE DIAMETER WITHIN 25% OF THE NORM.

July 3, 1973 J. F. G. HARRIS 3, SOLID BLENDS OF PEROXY COMPOUNDS AND PHOSPHATE V CONTAINING DETERGENT BASES Filed July 20, 1970 2 Sheets-Sheet 1 IRS FIG.3.

1i 2 15. FIGA.

Jwm/ Fesaaeim (v i E fi'igg ATTORNEY y 1973 J. F. G. HARRIS 3,743,600 SOLID BLENDS OF PEROXY COMPOUNDS AND PHOSPHATE CONTAINING DETERGENT BASES Filed July 20, 1970 2 Sheets-Sheet 2 J3 mu [imam/4N 62006 E //r/:/

INVENTOR ATTORNEY United States Patent O Int. (:1. c11a 7/18, 7/56 US. Cl. 252-95 10 Claims ABSTRACT OF THE DISCLOSURE A particulate detergent composition comprising phosphate containing detergent base and a solid blend of peroxy compounds comprising inorganic peroxidic compounds selected from the group consisting of percarbonates, perborates in the form of an active oxygen containing material consisting of substantially regular particles of which at least 80% by weight have diameters which vary by not substantially more than 25% from the average mean diameter of the inorganic peroxy compound particles. The perborate and percarbonate components manifest the bulk density of 1:3 times that of the detergent base and an average mean particle diameter within 25 of the norm.

CROSS REFERENCE This is a continuation-in-part of Ser. No. 613,011 filed Jan. 31, 1967, now abandoned.

DETAILED DESCRIPTION The invention relates to peroxy compounds and particularly to detergent compositions containing peroxy compounds.

This invention provides a particulate detergent composition comprising a major proportion, based on the weight of the detergent composition, of a homogeneous detergent base having a normal size distribution and consisting of substantially regular particles and, distributed therein, a minor proportion, based on the weight of the detergent composition, of an active oxygen containing compound or compounds in the form of an active oxygen containing material consisting of substantially regular particles of which at least 80% by weight have diameters which vary by not substantially more than 25% from the average particle diameter of the material, having a bulk density of from 100% to 300% of that of the detergent base and having an average particle diameter of where X has a value of from 0.4 to 0.7 and when P, B and B are as herein defined.

The symbols, P, B and B used herein denote numerical values equal, respectively, to the average particle size of the detergent base in mm. and the bulk density, measured as herein described in g./cc., of the active oxygencontaining material and of the detergent base. By a normal size distribution we mean a distribution which varies in a continuous manner and peaks at a point intermediate to the minimum and maximum particle size.

While compositions according to the invention must consist of substantially regular shape, we prefer them to be generally spherical. When we refer to the diameter of particles herein we mean the diameter as determined by conventional sieve analysis using a nest of sieves. Solid detergent compositions which comprise a blend of a minor proportion of a particulate active oxygen-containing compound and a major proportion of a homogeneous particulate material which contains the remaining constituents of the detergent composition (the detergent base) may tend to segregate. It is, however, desirable that the active oxygen containing compound remain distributed throughout the detergent composition. It has been proposed in the past to reduce the tendency of blends to segregate by ensuring that their various constituents have a similar size distribution. Active oxygen containing compounds often have a lower rate of solution than the detergent bases conventionally used and particles of a size which corresponds to the largest found in the detergent base may remain undissolved after the remainder of the composition has gone into solution. It may therefore be disadvantageous to attempt to reduce the tendency of such compositions to segregate by matching the particle size distribution of their constituents.

The detergent compositions provided by the present invention have excellent characteristics in relation to their tendency to segregate, particularly in comparison with similar blends in which the minor proportion has an average particle diameter outside the essential limits set forth above, and also have acceptable rates of solution.

Any phosphate containing detergent base having a normal particle size distribution may be used as the detergent base in the practice of this invention. For example, a preferred species of phosphated detergent base is that material known by the trade name Deepio marketed by Procter & Gamble, Cincinnati, Ohio, which is a mixture of 34% by weight sodium tripolyphosphate, 7% by Weight sodium silicate, 29% by weight sodium sulphate and minor ingredients, 23% by weight sodium dodecyl benzene sulfonate, the balance of the composition being Water. In this type detergent base which may either be cationic, anionic or non-ionic, it has been noted that phosphate builders may be added to detergents such as alkyl sulphates and alkane sulphonates to increase their detergent effciency as well as their anti-corrosive properties. Sodium hydrogen phosphate is claimed to be an efiective builder for a variety of sulfonic and sulfuric ester detergents as described in US. Pat. 2,383,502 to Quimby. Furthermore, mixtures of tetrasodium-p-phosphate and acid reacting salts which provide a pH of less than 7, have been used for the same purpose particularly with respect to detergents of the type described in Henderson et al. US. Pat. 2,279,314. Other detergent bases, therefore, which contain phosphate ions are particularly useful in the practice of this invention.

Preferably the minor proportion of the detergent composition comprises, substantially solely, one or more active-oxygen containing compounds. The preferred active oxygen containing compounds are inorganic peroxidic compounds for example alkali metal peroxidic compounds such as percarbonates, perborates, persulphates, perphosphates and perpyrophosphates.

It is preferred in the composition according to our invention, and particularly in the detergent composition described above, to use a detergent base which has an average particle size of from 0.1 to 1.0 mm. Alternatively or additionally it is desirable that the detergent base has a bulk density; measured as herein described, of from 0.2 to 0.6 g./cc. Preferably, the detergent base has an average particle size of from 0.3 to 0.7 and/or a bulk density of from 0.2 to 0.5 g./ cc.

The active oxygen-containing material is advantageously present in not more than 25%, preferably not more than 20%, by weight of the detergent composition and it advantageously also has a bulk density of from 100% to 270% of that of the detergent base. Particularly advantageously, this invention provides a particulate detergent composition comprising at least based on the weight of the detergent composition, of a homogeneous detergent base having a normal size distribution consisting of substantially regular particles having a particle size of from 0.1 to 1.0 mm. in diameter and a bulk density of 0.2 to 0.6 g./cc. and, distributed therein, not more than 25%, based on the weight of the detergent composition, of one or more alkali metal percarbonates or perborates consisting of substantially regular particles of which at least 80% by weight have diameters which vary by not substantially more than 25% from the average particle diameter of the percarbonate or perborate, having a bulk density of from 100% to 270% of that of the detergent base and having an average particle diameter of (2.5PX)(l+B -B mm. where X has a value of from 0.4 to 0.7 and P, B and E are as herein defined.

Detergent compositions provided in this last embodiment of the invention show, particularly, a reduced tendency to segregate. Preferably in these last detergent compositions, the detergent base has a bulk density of 0.2 to 0.5 g./ cc. and/ or has an average particle size of from 0.3 to 0.7 mm. in diameter. Preferably the alkali metal perborate or percarbonate has an average particle diameter expressed in mm. by the general formula referred to above wherein X is a numerical value of from 0.45 to 0.65.

According to one most advantageous embodiment thereof, the invention particularly provides detergent compositions where the detergent base has a bulk density of 0.2 to 0.5 g./cc. and an average particle size of from 0.3 to 0.7 mm. in diameter and the active oxygen containing compound or compounds is or are selected from alkali metal perborates and percarbonates and has or have an average particle diameter expressed in mm. by the general formula referred to above wherein X is a numerical value of from 0.45 to 0.65 and are present in not more than by Weight of the blend.

We have found that such detergent compositions have a degree of segregation measured as described hereafter of not substantially more than 20. When, hereafter, We use the term degree of segregation we mean that it has been so measured.

Amongst detergent compositions which have a degree of segregation of not substantially more than 20, it has been found that those in which the detergent base also has a bulk density of 0.25 to 0.4 g./cc. and an average particle size of from 0.35 to 0.55 mm. in diameter and in which the active oxygen containing compound has a bulk density of from 100% to 240% of that of the detergent base and an average particle diameter expressed in mm. by the formula referred to above wherein X is a numerical value of from 0.50 to 0.60, are particularly advantageous and have a degree of segregation not substantially more than 10.

Of these last compositions we prefer those in which the detergent base is that known by the trade name Deepio and the active oxygen containing compound is sodium percarbonate.

This invention also provides a process for the production of liquid compositions in which the soluble blends provided herein are dissolved and/or processes for the utilization of such compositions particularly cleaning processes for, for instance, textiles which comprise dissolving detergent compositions provided herein in an aqueous liquid and contacting the material to be cleaned with resulting solution, if desired at elevated temperatures, and separating the cleaned material from the solution.

The bulk density of particulate materials when referred to herein was measured as follows:

A truncated cone shaped hopper of stainless steel having a largest internal diameter of 53 mm., a smallest in ternal diameter of 21 mm., an axial height of 58 mm. and provided at its narrow end with a totally opening shutter, is clamped in the axially vertical position and filled with the particulate material until it overflows the top being levelled 01f without compression of the contents.

A cylindrical cup of stainless steel of internal diameter of 45.2 mm. and of about the same height and of 50 ml. capacity is placed vertically below the hopper, the lower end of the hopper being 65 mm. above the plane of the top of the cup and the cup is then filled to overflowing from the hopper and is levelled 01f without com pression of the contents. The apparent specific gravity by free flow (bulk density) is the weight in grams of the contents of the cup divided by 50 in g./ cc.

The accompanying drawings, which are merely diagrammatic and not to scale, illustrate the apparatus used to measure the degree of segregation, when quoted herein, of detergent blends.

FIGS. 1 and 2 represent, in plan and elevation respectively, hopper A which consists of an upper portion 11 which has a square horizontal section having each side 5 cm. long and a lower pyramidal portion 12 the apex of the pyramid being truncated so as to provide a rectangular opening 13, which has sides 2.5 and 0.5 cm. long, in the base of the hopper. The vertical distance from the base 111 of the pyramid to the opening 13 is 2.5 cm. The opening 13 comprises the hopper discharge means and is totally or partially closable by a shutter (not shown) sliding parallel to its longer sides.

FIGS. 3 and 4 represent, in elevational and plan view respectively, a further hopper B which is bounded by two identical trapezoidal sides 14 which lie in planes parallel to each other, and two identical rectangular sides 15. Each trapezoidal side has a longer parallel side 16 of 20.8 cm. in length, a shorter parallel side 17 of 1.1 cm. in length and an angle between each non-parallel side and the shorter parallel side of Each rectangular hopper side measures 3.8 cm. across its shorter sides 18. The base 119 of the hopper is open and comprises the hopper discharge means, being totally or partially closable by a shutter (not shown) sliding parallel to the short sides of the rectangular hopper sides.

FIGS. 5 and 6 represent, in elevation and plan respectively, a rectangular receiving vessel C standing upright in its base 20 which is 1.3 cms. in width. The base 20 which has openings 21, 22, 23 and 24 seen in FIG. 6 each of which is 0.9 cm. wide, extends across the whole width of the vessel and is totally or partially closable by means of a shutter (not shown) sliding parallel to the width of the base, and the base and the top of the vessel, which is open, each having along dimension of 28:8 cms. The vessel has a vertical height of 25.4 cms. Opening 21 has a centre point coinciding with that of the base of the vessel and openings 22, 23 and 24 have respectively, a centre point 3.4 cms., 6.0 cms. and 13.0 cms. from that of opening 21.

The apparatus illustrated in FIGS. 1-6 was employed to measure the degree of segregation of detergent blends as described below.

A thoroughly blended detergent composition comprising 117 g. of a phosphate containing detergent base referred to commercially as Deepio and described below in detail as to specific composition and 13 g. of an active oxygen containing compound such as sodium percarbonate was poured into hopper A, discharge means \13 being closed.

Hopper B was positioned with its closed discharge means 9 lower-most and in the horizontal plane. Hopper A was positioned so that its discharge means 13 lay in the plane of the mouth of hopper B, was symmetrically vertically above the discharged means and so that the long sides of openings 13 and 19 were all parallel, the shutters of each opening in the same direction.

Discharge means 13 was then partially opened so that the blend ran slowly into hopper B discharge means 19 being closed.

Hopper B was then positioned over upright receiving vessel C, discharge means 19 coinciding with the plane of the open top of vessel C, having its long sides parallel to those of the top of the receiving vessel and so that,

on partially opening discharge means 19 the resulting small opening was vertically above opening 21 of vessel C.

Discharge means 19 was then partially opened so as to allow the detergent blend to run slowly into vessel C openings 2-1, 22, 23 and 24 being closed. A sample of of the detergent bases used in the examples herein were inserted into the equation set forth in claim 1 herein and the value of X was calculated.

Detergent Base having a bulk density (Bd) of 0.30 and 5 about 38 cc. of detergent was taken from each of openan average Partlcle S126 (P) of 1ngs 21, 22, 23 and 24 and the percentage of active (2 5P X) (1 B B ti l i f oxygen containing compound in each, based on the total hydrate in mm. such content of all four samples, was determined by (2 30):O 58 chemical means. 10 A measure of the degree of segregation which has 5 fl taken place is given by the the width of the range of percentages so obtained. When were refer to the Degree 0.855=X gi ifigg found harem We refer to the figure thus 1 Such a blend would not be according to this invention. O V A blend, for example a detergent composition accordgl f i jg 8i ggg gg of gJcc' and aver ing to this invention may be prepared by reference to P the values of X obtained by inserting the relevant numeri- 0,58 cal values, for a number of particle size fractions of active oxygen-containing compound, into the equation 20 0 505 X (2.5PX(1+B -B )=particle size of active oxygen containing in mm., the values of P and E being those Such a blend would be according to this invention. corresponding to the detergent base it is intended to use T0 f t e ust te the present invention We have and the variation of bulk density with the average par- P p a number of different blends Containing 10% ticle size of the corresponding fractions of the active 25 y Weight of the aflive oXygen-containing Compound and oxygen containing compound having previously been dehave conducted tests, in the manner and using the aptermined. Blends containing the detergent base and a paratus described herein, to determine the degree of size fraction of active oxygen-containing compound havsegregation of these b ends. The composition of each ing an average particle size corresponding to a value of blend and the degree of segregation found are sum- X within those allowed herein are within the invention 30 marised in Table 1 herein. By referring to the values of provided that the remaining essential features of this X quoted in Table 1 it can be seen that blends Nos. 1, invention are complied with. 5-12, -18, -24, 27 and 28 are outside the scope of The active oxygen containing material to be used may the invention (they are inserted for comparative purposes be obtained by suitably sieving normally obtainable aconly) and blends 2, 3, 4, 13, 14, 19, and 26 are active oxygen containing material or, if material having a cording to the invention.

TABLE I Base detergent Active oxygen containing compound Bulk Average 100% density Degree particle Bulk within of average Average of segsize density Active oxygen range size value of regation Blend number (mm.) (g./cc.) compound (111111.) (g./cc.) X (Calo) (found) 0.53 0. 30 Sodium .710-.50 .55 .80 22 0. 53 0. 80 Carbonate. 85-. 71 54 70 14 0. 53 0. 30 Perhydrate 1. 0-. s5 .52 .57 7 0.53 0. 30 do 1.2-1.0 .50 .41 15 0.53 0. 30 Sodiun1 .15-. 075 .70 1. 245 53 0.53 0. 30 Perborate .21-. 15 .53 1.10 0.53 0. 30 Tetrahydrate .25-. 21 .05 1.15 47 0. 53 0. 30 355-. 25 e5 1. i0 43 0. 53 0. 30 5s 1. 02 35 0. 53 0. 30 70 0. 93 30 0.53 0. 30 .71 .55 20 0.53 0. a0 .72 .73 23 0.53 0. 30 .73 .55 21 0.53 0.50 .73 .50 1e 0. as 0.32 .03 .se 50 Deeplo" 67 84 53 Deepio .52 .80 47 Deepio 57 73 30 Deepio .50 .57 e Deepio .42 .32 33 Deepio .70 .89 53 Deepio .63 .84 40 Deepio .55 s0 40 Deepio" 66 75 33 Deepio .69 .03 1e Deepio 71 .45 11 Deepio 73 .32 24. "Deepio 74 13 40 limited particle size and bulk density is required, by processes as described in, or analogous to, those described in US. Pat. No. 3,463,618.

Example 12 of that patent describes the production of sodium carbonate perhydrate having a bulk density of 0.54 g./cc., determined by the same method as described herein, an average particle size of about 0.58 mm. and has a size distribution such that 92.8% by weight of the particles are between 0.353 mm. and 0.801 mm. in diameter. It is apparent from the particle size distribution disclosed that more than 80% by weight of the particles have diameters between 0.42 and 0.75 mm. As an illustration of this invention the relevant dimensions of the above described sodium carbonate perhydrate and each 7 being from 100% to 300% of the bulk density of the detergent base and the average particle diameter of the peroxy containing particles in millimeters being equal to wherein X has a value of from 0.4 to 0.7; P is the average particle size of the detergent base in millimeters; B is thebulk density of the peroxy containing particles in g./cc.; and E is the bulk density of the detergent base in g./cc., at least 8.0% by weight of the peroXy containing particles having diameters which vary by not substantially more than 25 of the average particle diameter.

2. A composition as claimed in claim 1 wherein the peroxy containing particles have a bulk density of from 100% to 270% of that of the detergent base.

3. A composition as claimed in claim 1 wherein the peroxy compounds are alkali metal percarbonates or perborates.

4. A composition as claimed in claim 1 wherein X has a value of from 0.45 to 0.65.

5. A process for cleaning textile materials comprising dissolving a composition as claimed in claim 1 in an aqueous liquid, contacting a textile material with the resulting solution and separating the material from the solution.

6. A composition as claimed in claim 2 wherein the detergent base has a bulk density of 0.25 to 0.4.

7. A particulate detergent composition consisting essentially of (a) at least 80%, by weight of the composition, of substantially regular particles of phosphated detergent base having an average particle size of from 0.35 to 0.55 mm. in diameter in normal siz distribution and a bulk density of from 0.25 to 0.4 g./ cc. and

(b) distributed therein, not more than 20% by weight of the composition, of substantially regular particles of at least one alkali metal percarbonate or perborate, the bulk density of the percarbonate or perborate being from 100% to 270% of the bulk density of the detergent base and the average particle diameter of the percarbonate or perborate in millimeters being equal to (2.5P-X) -(1+B B wherein X has a value of from 0.45 to 0.65; P is the average particle size of the detergent base in millimeters; B is the bulk density of the percarbonate or perborate in g./cc.; and B is the bulk density of the detergent based in g./cc., at least by weight of the peroxy containing particles having diameters which vary by not substantially more than 25% of the average particle diameter.

8. A composition as claimed in claim 7 wherein the alkali metal percarbonate or perborate has a bulk density of from to 240% of that of the detergent base.

9. A composition as claimed in claim '7 wherein the percarbonate or perborate particles have an average particle size such that X has a value of 0.50 to 0.60.

10. A composition as claimed in claim 9 wherein the alkali metal percarbonate or perborate has a bulk density of from 100% to 240% of that of the detergent base.

References Cited UNITED STATES PATENTS 2,975,142 3/1961 Schmidt et a1. 252-99 X 2,977,313 3/1961 Roland 252-99 3,338,671 8/1967 Marshall et al 25299 X MAYER 'WEINBLATT, Primary Examiner US. Cl. X.R. 

